My Vote for Bhagat Singh. The final aim of Gandhi and Bhagat Singh was same. And i would like to compare Gandhi and Mandela here.

Mandela supported Non-Violance, this resulted in unity and different nationalist with same goal worked for country.

In case of India, Bhagat Singh had respect for Gandhi but Gandhi never supported Bhagat Singh. And problem was Gandhi was more famous among public, if Gandhi had supported Bhagat Singh results would have been different.

As per me the Independance was achieved by these events:

Mangal Pandey

Bhagat Singh and Azaad

Netaji Subhash Chandra Bose (The final fighter, he actually won the part of North-East from England)